//===- LiveDebugVariables.cpp - Tracking debug info variables -------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This file implements the LiveDebugVariables analysis. // // Remove all DBG_VALUE instructions referencing virtual registers and replace // them with a data structure tracking where live user variables are kept - in a // virtual register or in a stack slot. // // Allow the data structure to be updated during register allocation when values // are moved between registers and stack slots. Finally emit new DBG_VALUE // instructions after register allocation is complete. // //===----------------------------------------------------------------------===// #include "LiveDebugVariables.h" #include "llvm/ADT/ArrayRef.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/IntervalMap.h" #include "llvm/ADT/MapVector.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" #include "llvm/ADT/StringRef.h" #include "llvm/CodeGen/LexicalScopes.h" #include "llvm/CodeGen/LiveInterval.h" #include "llvm/CodeGen/LiveIntervals.h" #include "llvm/CodeGen/MachineBasicBlock.h" #include "llvm/CodeGen/MachineDominators.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineOperand.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/SlotIndexes.h" #include "llvm/CodeGen/TargetInstrInfo.h" #include "llvm/CodeGen/TargetOpcodes.h" #include "llvm/CodeGen/TargetRegisterInfo.h" #include "llvm/CodeGen/TargetSubtargetInfo.h" #include "llvm/CodeGen/VirtRegMap.h" #include "llvm/Config/llvm-config.h" #include "llvm/IR/DebugInfoMetadata.h" #include "llvm/IR/DebugLoc.h" #include "llvm/IR/Function.h" #include "llvm/IR/Metadata.h" #include "llvm/InitializePasses.h" #include "llvm/MC/MCRegisterInfo.h" #include "llvm/Pass.h" #include "llvm/Support/Casting.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" #include #include #include #include #include using namespace llvm; #define DEBUG_TYPE "livedebugvars" static cl::opt EnableLDV("live-debug-variables", cl::init(true), cl::desc("Enable the live debug variables pass"), cl::Hidden); STATISTIC(NumInsertedDebugValues, "Number of DBG_VALUEs inserted"); STATISTIC(NumInsertedDebugLabels, "Number of DBG_LABELs inserted"); char LiveDebugVariables::ID = 0; INITIALIZE_PASS_BEGIN(LiveDebugVariables, DEBUG_TYPE, "Debug Variable Analysis", false, false) INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) INITIALIZE_PASS_DEPENDENCY(LiveIntervals) INITIALIZE_PASS_END(LiveDebugVariables, DEBUG_TYPE, "Debug Variable Analysis", false, false) void LiveDebugVariables::getAnalysisUsage(AnalysisUsage &AU) const { AU.addRequired(); AU.addRequiredTransitive(); AU.setPreservesAll(); MachineFunctionPass::getAnalysisUsage(AU); } LiveDebugVariables::LiveDebugVariables() : MachineFunctionPass(ID) { initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry()); } enum : unsigned { UndefLocNo = ~0U }; /// Describes a location by number along with some flags about the original /// usage of the location. class DbgValueLocation { public: DbgValueLocation(unsigned LocNo, bool WasIndirect) : LocNo(LocNo), WasIndirect(WasIndirect) { static_assert(sizeof(*this) == sizeof(unsigned), "bad bitfield packing"); assert(locNo() == LocNo && "location truncation"); } DbgValueLocation() : LocNo(0), WasIndirect(0) {} unsigned locNo() const { // Fix up the undef location number, which gets truncated. return LocNo == INT_MAX ? UndefLocNo : LocNo; } bool wasIndirect() const { return WasIndirect; } bool isUndef() const { return locNo() == UndefLocNo; } DbgValueLocation changeLocNo(unsigned NewLocNo) const { return DbgValueLocation(NewLocNo, WasIndirect); } friend inline bool operator==(const DbgValueLocation &LHS, const DbgValueLocation &RHS) { return LHS.LocNo == RHS.LocNo && LHS.WasIndirect == RHS.WasIndirect; } friend inline bool operator!=(const DbgValueLocation &LHS, const DbgValueLocation &RHS) { return !(LHS == RHS); } private: unsigned LocNo : 31; unsigned WasIndirect : 1; }; /// Map of where a user value is live, and its location. using LocMap = IntervalMap; /// Map of stack slot offsets for spilled locations. /// Non-spilled locations are not added to the map. using SpillOffsetMap = DenseMap; namespace { class LDVImpl; /// A user value is a part of a debug info user variable. /// /// A DBG_VALUE instruction notes that (a sub-register of) a virtual register /// holds part of a user variable. The part is identified by a byte offset. /// /// UserValues are grouped into equivalence classes for easier searching. Two /// user values are related if they refer to the same variable, or if they are /// held by the same virtual register. The equivalence class is the transitive /// closure of that relation. class UserValue { const DILocalVariable *Variable; ///< The debug info variable we are part of. const DIExpression *Expression; ///< Any complex address expression. DebugLoc dl; ///< The debug location for the variable. This is ///< used by dwarf writer to find lexical scope. UserValue *leader; ///< Equivalence class leader. UserValue *next = nullptr; ///< Next value in equivalence class, or null. /// Numbered locations referenced by locmap. SmallVector locations; /// Map of slot indices where this value is live. LocMap locInts; /// Set of interval start indexes that have been trimmed to the /// lexical scope. SmallSet trimmedDefs; /// Insert a DBG_VALUE into MBB at Idx for LocNo. void insertDebugValue(MachineBasicBlock *MBB, SlotIndex StartIdx, SlotIndex StopIdx, DbgValueLocation Loc, bool Spilled, unsigned SpillOffset, LiveIntervals &LIS, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI); /// Replace OldLocNo ranges with NewRegs ranges where NewRegs /// is live. Returns true if any changes were made. bool splitLocation(unsigned OldLocNo, ArrayRef NewRegs, LiveIntervals &LIS); public: /// Create a new UserValue. UserValue(const DILocalVariable *var, const DIExpression *expr, DebugLoc L, LocMap::Allocator &alloc) : Variable(var), Expression(expr), dl(std::move(L)), leader(this), locInts(alloc) {} /// Get the leader of this value's equivalence class. UserValue *getLeader() { UserValue *l = leader; while (l != l->leader) l = l->leader; return leader = l; } /// Return the next UserValue in the equivalence class. UserValue *getNext() const { return next; } /// Does this UserValue match the parameters? bool match(const DILocalVariable *Var, const DIExpression *Expr, const DILocation *IA) const { // FIXME: The fragment should be part of the equivalence class, but not // other things in the expression like stack values. return Var == Variable && Expr == Expression && dl->getInlinedAt() == IA; } /// Merge equivalence classes. static UserValue *merge(UserValue *L1, UserValue *L2) { L2 = L2->getLeader(); if (!L1) return L2; L1 = L1->getLeader(); if (L1 == L2) return L1; // Splice L2 before L1's members. UserValue *End = L2; while (End->next) { End->leader = L1; End = End->next; } End->leader = L1; End->next = L1->next; L1->next = L2; return L1; } /// Return the location number that matches Loc. /// /// For undef values we always return location number UndefLocNo without /// inserting anything in locations. Since locations is a vector and the /// location number is the position in the vector and UndefLocNo is ~0, /// we would need a very big vector to put the value at the right position. unsigned getLocationNo(const MachineOperand &LocMO) { if (LocMO.isReg()) { if (LocMO.getReg() == 0) return UndefLocNo; // For register locations we dont care about use/def and other flags. for (unsigned i = 0, e = locations.size(); i != e; ++i) if (locations[i].isReg() && locations[i].getReg() == LocMO.getReg() && locations[i].getSubReg() == LocMO.getSubReg()) return i; } else for (unsigned i = 0, e = locations.size(); i != e; ++i) if (LocMO.isIdenticalTo(locations[i])) return i; locations.push_back(LocMO); // We are storing a MachineOperand outside a MachineInstr. locations.back().clearParent(); // Don't store def operands. if (locations.back().isReg()) { if (locations.back().isDef()) locations.back().setIsDead(false); locations.back().setIsUse(); } return locations.size() - 1; } /// Remove (recycle) a location number. If \p LocNo still is used by the /// locInts nothing is done. void removeLocationIfUnused(unsigned LocNo) { // Bail out if LocNo still is used. for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) { DbgValueLocation Loc = I.value(); if (Loc.locNo() == LocNo) return; } // Remove the entry in the locations vector, and adjust all references to // location numbers above the removed entry. locations.erase(locations.begin() + LocNo); for (LocMap::iterator I = locInts.begin(); I.valid(); ++I) { DbgValueLocation Loc = I.value(); if (!Loc.isUndef() && Loc.locNo() > LocNo) I.setValueUnchecked(Loc.changeLocNo(Loc.locNo() - 1)); } } /// Ensure that all virtual register locations are mapped. void mapVirtRegs(LDVImpl *LDV); /// Add a definition point to this value. void addDef(SlotIndex Idx, const MachineOperand &LocMO, bool IsIndirect) { DbgValueLocation Loc(getLocationNo(LocMO), IsIndirect); // Add a singular (Idx,Idx) -> Loc mapping. LocMap::iterator I = locInts.find(Idx); if (!I.valid() || I.start() != Idx) I.insert(Idx, Idx.getNextSlot(), Loc); else // A later DBG_VALUE at the same SlotIndex overrides the old location. I.setValue(Loc); } /// Extend the current definition as far as possible down. /// /// Stop when meeting an existing def or when leaving the live /// range of VNI. End points where VNI is no longer live are added to Kills. /// /// We only propagate DBG_VALUES locally here. LiveDebugValues performs a /// data-flow analysis to propagate them beyond basic block boundaries. /// /// \param Idx Starting point for the definition. /// \param Loc Location number to propagate. /// \param LR Restrict liveness to where LR has the value VNI. May be null. /// \param VNI When LR is not null, this is the value to restrict to. /// \param [out] Kills Append end points of VNI's live range to Kills. /// \param LIS Live intervals analysis. void extendDef(SlotIndex Idx, DbgValueLocation Loc, LiveRange *LR, const VNInfo *VNI, SmallVectorImpl *Kills, LiveIntervals &LIS); /// The value in LI/LocNo may be copies to other registers. Determine if /// any of the copies are available at the kill points, and add defs if /// possible. /// /// \param LI Scan for copies of the value in LI->reg. /// \param LocNo Location number of LI->reg. /// \param WasIndirect Indicates if the original use of LI->reg was indirect /// \param Kills Points where the range of LocNo could be extended. /// \param [in,out] NewDefs Append (Idx, LocNo) of inserted defs here. void addDefsFromCopies( LiveInterval *LI, unsigned LocNo, bool WasIndirect, const SmallVectorImpl &Kills, SmallVectorImpl> &NewDefs, MachineRegisterInfo &MRI, LiveIntervals &LIS); /// Compute the live intervals of all locations after collecting all their /// def points. void computeIntervals(MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI, LiveIntervals &LIS, LexicalScopes &LS); /// Replace OldReg ranges with NewRegs ranges where NewRegs is /// live. Returns true if any changes were made. bool splitRegister(unsigned OldReg, ArrayRef NewRegs, LiveIntervals &LIS); /// Rewrite virtual register locations according to the provided virtual /// register map. Record the stack slot offsets for the locations that /// were spilled. void rewriteLocations(VirtRegMap &VRM, const MachineFunction &MF, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI, SpillOffsetMap &SpillOffsets); /// Recreate DBG_VALUE instruction from data structures. void emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI, const SpillOffsetMap &SpillOffsets); /// Return DebugLoc of this UserValue. DebugLoc getDebugLoc() { return dl;} void print(raw_ostream &, const TargetRegisterInfo *); }; /// A user label is a part of a debug info user label. class UserLabel { const DILabel *Label; ///< The debug info label we are part of. DebugLoc dl; ///< The debug location for the label. This is ///< used by dwarf writer to find lexical scope. SlotIndex loc; ///< Slot used by the debug label. /// Insert a DBG_LABEL into MBB at Idx. void insertDebugLabel(MachineBasicBlock *MBB, SlotIndex Idx, LiveIntervals &LIS, const TargetInstrInfo &TII); public: /// Create a new UserLabel. UserLabel(const DILabel *label, DebugLoc L, SlotIndex Idx) : Label(label), dl(std::move(L)), loc(Idx) {} /// Does this UserLabel match the parameters? bool match(const DILabel *L, const DILocation *IA, const SlotIndex Index) const { return Label == L && dl->getInlinedAt() == IA && loc == Index; } /// Recreate DBG_LABEL instruction from data structures. void emitDebugLabel(LiveIntervals &LIS, const TargetInstrInfo &TII); /// Return DebugLoc of this UserLabel. DebugLoc getDebugLoc() { return dl; } void print(raw_ostream &, const TargetRegisterInfo *); }; /// Implementation of the LiveDebugVariables pass. class LDVImpl { LiveDebugVariables &pass; LocMap::Allocator allocator; MachineFunction *MF = nullptr; LiveIntervals *LIS; const TargetRegisterInfo *TRI; /// Whether emitDebugValues is called. bool EmitDone = false; /// Whether the machine function is modified during the pass. bool ModifiedMF = false; /// All allocated UserValue instances. SmallVector, 8> userValues; /// All allocated UserLabel instances. SmallVector, 2> userLabels; /// Map virtual register to eq class leader. using VRMap = DenseMap; VRMap virtRegToEqClass; /// Map user variable to eq class leader. using UVMap = DenseMap; UVMap userVarMap; /// Find or create a UserValue. UserValue *getUserValue(const DILocalVariable *Var, const DIExpression *Expr, const DebugLoc &DL); /// Find the EC leader for VirtReg or null. UserValue *lookupVirtReg(unsigned VirtReg); /// Add DBG_VALUE instruction to our maps. /// /// \param MI DBG_VALUE instruction /// \param Idx Last valid SLotIndex before instruction. /// /// \returns True if the DBG_VALUE instruction should be deleted. bool handleDebugValue(MachineInstr &MI, SlotIndex Idx); /// Add DBG_LABEL instruction to UserLabel. /// /// \param MI DBG_LABEL instruction /// \param Idx Last valid SlotIndex before instruction. /// /// \returns True if the DBG_LABEL instruction should be deleted. bool handleDebugLabel(MachineInstr &MI, SlotIndex Idx); /// Collect and erase all DBG_VALUE instructions, adding a UserValue def /// for each instruction. /// /// \param mf MachineFunction to be scanned. /// /// \returns True if any debug values were found. bool collectDebugValues(MachineFunction &mf); /// Compute the live intervals of all user values after collecting all /// their def points. void computeIntervals(); public: LDVImpl(LiveDebugVariables *ps) : pass(*ps) {} bool runOnMachineFunction(MachineFunction &mf); /// Release all memory. void clear() { MF = nullptr; userValues.clear(); userLabels.clear(); virtRegToEqClass.clear(); userVarMap.clear(); // Make sure we call emitDebugValues if the machine function was modified. assert((!ModifiedMF || EmitDone) && "Dbg values are not emitted in LDV"); EmitDone = false; ModifiedMF = false; } /// Map virtual register to an equivalence class. void mapVirtReg(unsigned VirtReg, UserValue *EC); /// Replace all references to OldReg with NewRegs. void splitRegister(unsigned OldReg, ArrayRef NewRegs); /// Recreate DBG_VALUE instruction from data structures. void emitDebugValues(VirtRegMap *VRM); void print(raw_ostream&); }; } // end anonymous namespace #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) static void printDebugLoc(const DebugLoc &DL, raw_ostream &CommentOS, const LLVMContext &Ctx) { if (!DL) return; auto *Scope = cast(DL.getScope()); // Omit the directory, because it's likely to be long and uninteresting. CommentOS << Scope->getFilename(); CommentOS << ':' << DL.getLine(); if (DL.getCol() != 0) CommentOS << ':' << DL.getCol(); DebugLoc InlinedAtDL = DL.getInlinedAt(); if (!InlinedAtDL) return; CommentOS << " @[ "; printDebugLoc(InlinedAtDL, CommentOS, Ctx); CommentOS << " ]"; } static void printExtendedName(raw_ostream &OS, const DINode *Node, const DILocation *DL) { const LLVMContext &Ctx = Node->getContext(); StringRef Res; unsigned Line = 0; if (const auto *V = dyn_cast(Node)) { Res = V->getName(); Line = V->getLine(); } else if (const auto *L = dyn_cast(Node)) { Res = L->getName(); Line = L->getLine(); } if (!Res.empty()) OS << Res << "," << Line; auto *InlinedAt = DL ? DL->getInlinedAt() : nullptr; if (InlinedAt) { if (DebugLoc InlinedAtDL = InlinedAt) { OS << " @["; printDebugLoc(InlinedAtDL, OS, Ctx); OS << "]"; } } } void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) { OS << "!\""; printExtendedName(OS, Variable, dl); OS << "\"\t"; for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) { OS << " [" << I.start() << ';' << I.stop() << "):"; if (I.value().isUndef()) OS << "undef"; else { OS << I.value().locNo(); if (I.value().wasIndirect()) OS << " ind"; } } for (unsigned i = 0, e = locations.size(); i != e; ++i) { OS << " Loc" << i << '='; locations[i].print(OS, TRI); } OS << '\n'; } void UserLabel::print(raw_ostream &OS, const TargetRegisterInfo *TRI) { OS << "!\""; printExtendedName(OS, Label, dl); OS << "\"\t"; OS << loc; OS << '\n'; } void LDVImpl::print(raw_ostream &OS) { OS << "********** DEBUG VARIABLES **********\n"; for (auto &userValue : userValues) userValue->print(OS, TRI); OS << "********** DEBUG LABELS **********\n"; for (auto &userLabel : userLabels) userLabel->print(OS, TRI); } #endif void UserValue::mapVirtRegs(LDVImpl *LDV) { for (unsigned i = 0, e = locations.size(); i != e; ++i) if (locations[i].isReg() && Register::isVirtualRegister(locations[i].getReg())) LDV->mapVirtReg(locations[i].getReg(), this); } UserValue *LDVImpl::getUserValue(const DILocalVariable *Var, const DIExpression *Expr, const DebugLoc &DL) { UserValue *&Leader = userVarMap[Var]; if (Leader) { UserValue *UV = Leader->getLeader(); Leader = UV; for (; UV; UV = UV->getNext()) if (UV->match(Var, Expr, DL->getInlinedAt())) return UV; } userValues.push_back( std::make_unique(Var, Expr, DL, allocator)); UserValue *UV = userValues.back().get(); Leader = UserValue::merge(Leader, UV); return UV; } void LDVImpl::mapVirtReg(unsigned VirtReg, UserValue *EC) { assert(Register::isVirtualRegister(VirtReg) && "Only map VirtRegs"); UserValue *&Leader = virtRegToEqClass[VirtReg]; Leader = UserValue::merge(Leader, EC); } UserValue *LDVImpl::lookupVirtReg(unsigned VirtReg) { if (UserValue *UV = virtRegToEqClass.lookup(VirtReg)) return UV->getLeader(); return nullptr; } bool LDVImpl::handleDebugValue(MachineInstr &MI, SlotIndex Idx) { // DBG_VALUE loc, offset, variable if (MI.getNumOperands() != 4 || !(MI.getOperand(1).isReg() || MI.getOperand(1).isImm()) || !MI.getOperand(2).isMetadata()) { LLVM_DEBUG(dbgs() << "Can't handle " << MI); return false; } // Detect invalid DBG_VALUE instructions, with a debug-use of a virtual // register that hasn't been defined yet. If we do not remove those here, then // the re-insertion of the DBG_VALUE instruction after register allocation // will be incorrect. // TODO: If earlier passes are corrected to generate sane debug information // (and if the machine verifier is improved to catch this), then these checks // could be removed or replaced by asserts. bool Discard = false; if (MI.getOperand(0).isReg() && Register::isVirtualRegister(MI.getOperand(0).getReg())) { const Register Reg = MI.getOperand(0).getReg(); if (!LIS->hasInterval(Reg)) { // The DBG_VALUE is described by a virtual register that does not have a // live interval. Discard the DBG_VALUE. Discard = true; LLVM_DEBUG(dbgs() << "Discarding debug info (no LIS interval): " << Idx << " " << MI); } else { // The DBG_VALUE is only valid if either Reg is live out from Idx, or Reg // is defined dead at Idx (where Idx is the slot index for the instruction // preceding the DBG_VALUE). const LiveInterval &LI = LIS->getInterval(Reg); LiveQueryResult LRQ = LI.Query(Idx); if (!LRQ.valueOutOrDead()) { // We have found a DBG_VALUE with the value in a virtual register that // is not live. Discard the DBG_VALUE. Discard = true; LLVM_DEBUG(dbgs() << "Discarding debug info (reg not live): " << Idx << " " << MI); } } } // Get or create the UserValue for (variable,offset) here. bool IsIndirect = MI.getOperand(1).isImm(); if (IsIndirect) assert(MI.getOperand(1).getImm() == 0 && "DBG_VALUE with nonzero offset"); const DILocalVariable *Var = MI.getDebugVariable(); const DIExpression *Expr = MI.getDebugExpression(); UserValue *UV = getUserValue(Var, Expr, MI.getDebugLoc()); if (!Discard) UV->addDef(Idx, MI.getOperand(0), IsIndirect); else { MachineOperand MO = MachineOperand::CreateReg(0U, false); MO.setIsDebug(); UV->addDef(Idx, MO, false); } return true; } bool LDVImpl::handleDebugLabel(MachineInstr &MI, SlotIndex Idx) { // DBG_LABEL label if (MI.getNumOperands() != 1 || !MI.getOperand(0).isMetadata()) { LLVM_DEBUG(dbgs() << "Can't handle " << MI); return false; } // Get or create the UserLabel for label here. const DILabel *Label = MI.getDebugLabel(); const DebugLoc &DL = MI.getDebugLoc(); bool Found = false; for (auto const &L : userLabels) { if (L->match(Label, DL->getInlinedAt(), Idx)) { Found = true; break; } } if (!Found) userLabels.push_back(std::make_unique(Label, DL, Idx)); return true; } bool LDVImpl::collectDebugValues(MachineFunction &mf) { bool Changed = false; for (MachineFunction::iterator MFI = mf.begin(), MFE = mf.end(); MFI != MFE; ++MFI) { MachineBasicBlock *MBB = &*MFI; for (MachineBasicBlock::iterator MBBI = MBB->begin(), MBBE = MBB->end(); MBBI != MBBE;) { // Use the first debug instruction in the sequence to get a SlotIndex // for following consecutive debug instructions. if (!MBBI->isDebugInstr()) { ++MBBI; continue; } // Debug instructions has no slot index. Use the previous // non-debug instruction's SlotIndex as its SlotIndex. SlotIndex Idx = MBBI == MBB->begin() ? LIS->getMBBStartIdx(MBB) : LIS->getInstructionIndex(*std::prev(MBBI)).getRegSlot(); // Handle consecutive debug instructions with the same slot index. do { // Only handle DBG_VALUE in handleDebugValue(). Skip all other // kinds of debug instructions. if ((MBBI->isDebugValue() && handleDebugValue(*MBBI, Idx)) || (MBBI->isDebugLabel() && handleDebugLabel(*MBBI, Idx))) { MBBI = MBB->erase(MBBI); Changed = true; } else ++MBBI; } while (MBBI != MBBE && MBBI->isDebugInstr()); } } return Changed; } void UserValue::extendDef(SlotIndex Idx, DbgValueLocation Loc, LiveRange *LR, const VNInfo *VNI, SmallVectorImpl *Kills, LiveIntervals &LIS) { SlotIndex Start = Idx; MachineBasicBlock *MBB = LIS.getMBBFromIndex(Start); SlotIndex Stop = LIS.getMBBEndIdx(MBB); LocMap::iterator I = locInts.find(Start); // Limit to VNI's live range. bool ToEnd = true; if (LR && VNI) { LiveInterval::Segment *Segment = LR->getSegmentContaining(Start); if (!Segment || Segment->valno != VNI) { if (Kills) Kills->push_back(Start); return; } if (Segment->end < Stop) { Stop = Segment->end; ToEnd = false; } } // There could already be a short def at Start. if (I.valid() && I.start() <= Start) { // Stop when meeting a different location or an already extended interval. Start = Start.getNextSlot(); if (I.value() != Loc || I.stop() != Start) return; // This is a one-slot placeholder. Just skip it. ++I; } // Limited by the next def. if (I.valid() && I.start() < Stop) Stop = I.start(); // Limited by VNI's live range. else if (!ToEnd && Kills) Kills->push_back(Stop); if (Start < Stop) I.insert(Start, Stop, Loc); } void UserValue::addDefsFromCopies( LiveInterval *LI, unsigned LocNo, bool WasIndirect, const SmallVectorImpl &Kills, SmallVectorImpl> &NewDefs, MachineRegisterInfo &MRI, LiveIntervals &LIS) { if (Kills.empty()) return; // Don't track copies from physregs, there are too many uses. if (!Register::isVirtualRegister(LI->reg)) return; // Collect all the (vreg, valno) pairs that are copies of LI. SmallVector, 8> CopyValues; for (MachineOperand &MO : MRI.use_nodbg_operands(LI->reg)) { MachineInstr *MI = MO.getParent(); // Copies of the full value. if (MO.getSubReg() || !MI->isCopy()) continue; Register DstReg = MI->getOperand(0).getReg(); // Don't follow copies to physregs. These are usually setting up call // arguments, and the argument registers are always call clobbered. We are // better off in the source register which could be a callee-saved register, // or it could be spilled. if (!Register::isVirtualRegister(DstReg)) continue; // Is LocNo extended to reach this copy? If not, another def may be blocking // it, or we are looking at a wrong value of LI. SlotIndex Idx = LIS.getInstructionIndex(*MI); LocMap::iterator I = locInts.find(Idx.getRegSlot(true)); if (!I.valid() || I.value().locNo() != LocNo) continue; if (!LIS.hasInterval(DstReg)) continue; LiveInterval *DstLI = &LIS.getInterval(DstReg); const VNInfo *DstVNI = DstLI->getVNInfoAt(Idx.getRegSlot()); assert(DstVNI && DstVNI->def == Idx.getRegSlot() && "Bad copy value"); CopyValues.push_back(std::make_pair(DstLI, DstVNI)); } if (CopyValues.empty()) return; LLVM_DEBUG(dbgs() << "Got " << CopyValues.size() << " copies of " << *LI << '\n'); // Try to add defs of the copied values for each kill point. for (unsigned i = 0, e = Kills.size(); i != e; ++i) { SlotIndex Idx = Kills[i]; for (unsigned j = 0, e = CopyValues.size(); j != e; ++j) { LiveInterval *DstLI = CopyValues[j].first; const VNInfo *DstVNI = CopyValues[j].second; if (DstLI->getVNInfoAt(Idx) != DstVNI) continue; // Check that there isn't already a def at Idx LocMap::iterator I = locInts.find(Idx); if (I.valid() && I.start() <= Idx) continue; LLVM_DEBUG(dbgs() << "Kill at " << Idx << " covered by valno #" << DstVNI->id << " in " << *DstLI << '\n'); MachineInstr *CopyMI = LIS.getInstructionFromIndex(DstVNI->def); assert(CopyMI && CopyMI->isCopy() && "Bad copy value"); unsigned LocNo = getLocationNo(CopyMI->getOperand(0)); DbgValueLocation NewLoc(LocNo, WasIndirect); I.insert(Idx, Idx.getNextSlot(), NewLoc); NewDefs.push_back(std::make_pair(Idx, NewLoc)); break; } } } void UserValue::computeIntervals(MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI, LiveIntervals &LIS, LexicalScopes &LS) { SmallVector, 16> Defs; // Collect all defs to be extended (Skipping undefs). for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) if (!I.value().isUndef()) Defs.push_back(std::make_pair(I.start(), I.value())); // Extend all defs, and possibly add new ones along the way. for (unsigned i = 0; i != Defs.size(); ++i) { SlotIndex Idx = Defs[i].first; DbgValueLocation Loc = Defs[i].second; const MachineOperand &LocMO = locations[Loc.locNo()]; if (!LocMO.isReg()) { extendDef(Idx, Loc, nullptr, nullptr, nullptr, LIS); continue; } // Register locations are constrained to where the register value is live. if (Register::isVirtualRegister(LocMO.getReg())) { LiveInterval *LI = nullptr; const VNInfo *VNI = nullptr; if (LIS.hasInterval(LocMO.getReg())) { LI = &LIS.getInterval(LocMO.getReg()); VNI = LI->getVNInfoAt(Idx); } SmallVector Kills; extendDef(Idx, Loc, LI, VNI, &Kills, LIS); // FIXME: Handle sub-registers in addDefsFromCopies. The problem is that // if the original location for example is %vreg0:sub_hi, and we find a // full register copy in addDefsFromCopies (at the moment it only handles // full register copies), then we must add the sub1 sub-register index to // the new location. However, that is only possible if the new virtual // register is of the same regclass (or if there is an equivalent // sub-register in that regclass). For now, simply skip handling copies if // a sub-register is involved. if (LI && !LocMO.getSubReg()) addDefsFromCopies(LI, Loc.locNo(), Loc.wasIndirect(), Kills, Defs, MRI, LIS); continue; } // For physregs, we only mark the start slot idx. DwarfDebug will see it // as if the DBG_VALUE is valid up until the end of the basic block, or // the next def of the physical register. So we do not need to extend the // range. It might actually happen that the DBG_VALUE is the last use of // the physical register (e.g. if this is an unused input argument to a // function). } // The computed intervals may extend beyond the range of the debug // location's lexical scope. In this case, splitting of an interval // can result in an interval outside of the scope being created, // causing extra unnecessary DBG_VALUEs to be emitted. To prevent // this, trim the intervals to the lexical scope. LexicalScope *Scope = LS.findLexicalScope(dl); if (!Scope) return; SlotIndex PrevEnd; LocMap::iterator I = locInts.begin(); // Iterate over the lexical scope ranges. Each time round the loop // we check the intervals for overlap with the end of the previous // range and the start of the next. The first range is handled as // a special case where there is no PrevEnd. for (const InsnRange &Range : Scope->getRanges()) { SlotIndex RStart = LIS.getInstructionIndex(*Range.first); SlotIndex REnd = LIS.getInstructionIndex(*Range.second); // Variable locations at the first instruction of a block should be // based on the block's SlotIndex, not the first instruction's index. if (Range.first == Range.first->getParent()->begin()) RStart = LIS.getSlotIndexes()->getIndexBefore(*Range.first); // At the start of each iteration I has been advanced so that // I.stop() >= PrevEnd. Check for overlap. if (PrevEnd && I.start() < PrevEnd) { SlotIndex IStop = I.stop(); DbgValueLocation Loc = I.value(); // Stop overlaps previous end - trim the end of the interval to // the scope range. I.setStopUnchecked(PrevEnd); ++I; // If the interval also overlaps the start of the "next" (i.e. // current) range create a new interval for the remainder (which // may be further trimmed). if (RStart < IStop) I.insert(RStart, IStop, Loc); } // Advance I so that I.stop() >= RStart, and check for overlap. I.advanceTo(RStart); if (!I.valid()) return; if (I.start() < RStart) { // Interval start overlaps range - trim to the scope range. I.setStartUnchecked(RStart); // Remember that this interval was trimmed. trimmedDefs.insert(RStart); } // The end of a lexical scope range is the last instruction in the // range. To convert to an interval we need the index of the // instruction after it. REnd = REnd.getNextIndex(); // Advance I to first interval outside current range. I.advanceTo(REnd); if (!I.valid()) return; PrevEnd = REnd; } // Check for overlap with end of final range. if (PrevEnd && I.start() < PrevEnd) I.setStopUnchecked(PrevEnd); } void LDVImpl::computeIntervals() { LexicalScopes LS; LS.initialize(*MF); for (unsigned i = 0, e = userValues.size(); i != e; ++i) { userValues[i]->computeIntervals(MF->getRegInfo(), *TRI, *LIS, LS); userValues[i]->mapVirtRegs(this); } } bool LDVImpl::runOnMachineFunction(MachineFunction &mf) { clear(); MF = &mf; LIS = &pass.getAnalysis(); TRI = mf.getSubtarget().getRegisterInfo(); LLVM_DEBUG(dbgs() << "********** COMPUTING LIVE DEBUG VARIABLES: " << mf.getName() << " **********\n"); bool Changed = collectDebugValues(mf); computeIntervals(); LLVM_DEBUG(print(dbgs())); ModifiedMF = Changed; return Changed; } static void removeDebugValues(MachineFunction &mf) { for (MachineBasicBlock &MBB : mf) { for (auto MBBI = MBB.begin(), MBBE = MBB.end(); MBBI != MBBE; ) { if (!MBBI->isDebugValue()) { ++MBBI; continue; } MBBI = MBB.erase(MBBI); } } } bool LiveDebugVariables::runOnMachineFunction(MachineFunction &mf) { if (!EnableLDV) return false; if (!mf.getFunction().getSubprogram()) { removeDebugValues(mf); return false; } if (!pImpl) pImpl = new LDVImpl(this); return static_cast(pImpl)->runOnMachineFunction(mf); } void LiveDebugVariables::releaseMemory() { if (pImpl) static_cast(pImpl)->clear(); } LiveDebugVariables::~LiveDebugVariables() { if (pImpl) delete static_cast(pImpl); } //===----------------------------------------------------------------------===// // Live Range Splitting //===----------------------------------------------------------------------===// bool UserValue::splitLocation(unsigned OldLocNo, ArrayRef NewRegs, LiveIntervals& LIS) { LLVM_DEBUG({ dbgs() << "Splitting Loc" << OldLocNo << '\t'; print(dbgs(), nullptr); }); bool DidChange = false; LocMap::iterator LocMapI; LocMapI.setMap(locInts); for (unsigned i = 0; i != NewRegs.size(); ++i) { LiveInterval *LI = &LIS.getInterval(NewRegs[i]); if (LI->empty()) continue; // Don't allocate the new LocNo until it is needed. unsigned NewLocNo = UndefLocNo; // Iterate over the overlaps between locInts and LI. LocMapI.find(LI->beginIndex()); if (!LocMapI.valid()) continue; LiveInterval::iterator LII = LI->advanceTo(LI->begin(), LocMapI.start()); LiveInterval::iterator LIE = LI->end(); while (LocMapI.valid() && LII != LIE) { // At this point, we know that LocMapI.stop() > LII->start. LII = LI->advanceTo(LII, LocMapI.start()); if (LII == LIE) break; // Now LII->end > LocMapI.start(). Do we have an overlap? if (LocMapI.value().locNo() == OldLocNo && LII->start < LocMapI.stop()) { // Overlapping correct location. Allocate NewLocNo now. if (NewLocNo == UndefLocNo) { MachineOperand MO = MachineOperand::CreateReg(LI->reg, false); MO.setSubReg(locations[OldLocNo].getSubReg()); NewLocNo = getLocationNo(MO); DidChange = true; } SlotIndex LStart = LocMapI.start(); SlotIndex LStop = LocMapI.stop(); DbgValueLocation OldLoc = LocMapI.value(); // Trim LocMapI down to the LII overlap. if (LStart < LII->start) LocMapI.setStartUnchecked(LII->start); if (LStop > LII->end) LocMapI.setStopUnchecked(LII->end); // Change the value in the overlap. This may trigger coalescing. LocMapI.setValue(OldLoc.changeLocNo(NewLocNo)); // Re-insert any removed OldLocNo ranges. if (LStart < LocMapI.start()) { LocMapI.insert(LStart, LocMapI.start(), OldLoc); ++LocMapI; assert(LocMapI.valid() && "Unexpected coalescing"); } if (LStop > LocMapI.stop()) { ++LocMapI; LocMapI.insert(LII->end, LStop, OldLoc); --LocMapI; } } // Advance to the next overlap. if (LII->end < LocMapI.stop()) { if (++LII == LIE) break; LocMapI.advanceTo(LII->start); } else { ++LocMapI; if (!LocMapI.valid()) break; LII = LI->advanceTo(LII, LocMapI.start()); } } } // Finally, remove OldLocNo unless it is still used by some interval in the // locInts map. One case when OldLocNo still is in use is when the register // has been spilled. In such situations the spilled register is kept as a // location until rewriteLocations is called (VirtRegMap is mapping the old // register to the spill slot). So for a while we can have locations that map // to virtual registers that have been removed from both the MachineFunction // and from LiveIntervals. removeLocationIfUnused(OldLocNo); LLVM_DEBUG({ dbgs() << "Split result: \t"; print(dbgs(), nullptr); }); return DidChange; } bool UserValue::splitRegister(unsigned OldReg, ArrayRef NewRegs, LiveIntervals &LIS) { bool DidChange = false; // Split locations referring to OldReg. Iterate backwards so splitLocation can // safely erase unused locations. for (unsigned i = locations.size(); i ; --i) { unsigned LocNo = i-1; const MachineOperand *Loc = &locations[LocNo]; if (!Loc->isReg() || Loc->getReg() != OldReg) continue; DidChange |= splitLocation(LocNo, NewRegs, LIS); } return DidChange; } void LDVImpl::splitRegister(unsigned OldReg, ArrayRef NewRegs) { bool DidChange = false; for (UserValue *UV = lookupVirtReg(OldReg); UV; UV = UV->getNext()) DidChange |= UV->splitRegister(OldReg, NewRegs, *LIS); if (!DidChange) return; // Map all of the new virtual registers. UserValue *UV = lookupVirtReg(OldReg); for (unsigned i = 0; i != NewRegs.size(); ++i) mapVirtReg(NewRegs[i], UV); } void LiveDebugVariables:: splitRegister(unsigned OldReg, ArrayRef NewRegs, LiveIntervals &LIS) { if (pImpl) static_cast(pImpl)->splitRegister(OldReg, NewRegs); } void UserValue::rewriteLocations(VirtRegMap &VRM, const MachineFunction &MF, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI, SpillOffsetMap &SpillOffsets) { // Build a set of new locations with new numbers so we can coalesce our // IntervalMap if two vreg intervals collapse to the same physical location. // Use MapVector instead of SetVector because MapVector::insert returns the // position of the previously or newly inserted element. The boolean value // tracks if the location was produced by a spill. // FIXME: This will be problematic if we ever support direct and indirect // frame index locations, i.e. expressing both variables in memory and // 'int x, *px = &x'. The "spilled" bit must become part of the location. MapVector> NewLocations; SmallVector LocNoMap(locations.size()); for (unsigned I = 0, E = locations.size(); I != E; ++I) { bool Spilled = false; unsigned SpillOffset = 0; MachineOperand Loc = locations[I]; // Only virtual registers are rewritten. if (Loc.isReg() && Loc.getReg() && Register::isVirtualRegister(Loc.getReg())) { Register VirtReg = Loc.getReg(); if (VRM.isAssignedReg(VirtReg) && Register::isPhysicalRegister(VRM.getPhys(VirtReg))) { // This can create a %noreg operand in rare cases when the sub-register // index is no longer available. That means the user value is in a // non-existent sub-register, and %noreg is exactly what we want. Loc.substPhysReg(VRM.getPhys(VirtReg), TRI); } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT) { // Retrieve the stack slot offset. unsigned SpillSize; const MachineRegisterInfo &MRI = MF.getRegInfo(); const TargetRegisterClass *TRC = MRI.getRegClass(VirtReg); bool Success = TII.getStackSlotRange(TRC, Loc.getSubReg(), SpillSize, SpillOffset, MF); // FIXME: Invalidate the location if the offset couldn't be calculated. (void)Success; Loc = MachineOperand::CreateFI(VRM.getStackSlot(VirtReg)); Spilled = true; } else { Loc.setReg(0); Loc.setSubReg(0); } } // Insert this location if it doesn't already exist and record a mapping // from the old number to the new number. auto InsertResult = NewLocations.insert({Loc, {Spilled, SpillOffset}}); unsigned NewLocNo = std::distance(NewLocations.begin(), InsertResult.first); LocNoMap[I] = NewLocNo; } // Rewrite the locations and record the stack slot offsets for spills. locations.clear(); SpillOffsets.clear(); for (auto &Pair : NewLocations) { bool Spilled; unsigned SpillOffset; std::tie(Spilled, SpillOffset) = Pair.second; locations.push_back(Pair.first); if (Spilled) { unsigned NewLocNo = std::distance(&*NewLocations.begin(), &Pair); SpillOffsets[NewLocNo] = SpillOffset; } } // Update the interval map, but only coalesce left, since intervals to the // right use the old location numbers. This should merge two contiguous // DBG_VALUE intervals with different vregs that were allocated to the same // physical register. for (LocMap::iterator I = locInts.begin(); I.valid(); ++I) { DbgValueLocation Loc = I.value(); // Undef values don't exist in locations (and thus not in LocNoMap either) // so skip over them. See getLocationNo(). if (Loc.isUndef()) continue; unsigned NewLocNo = LocNoMap[Loc.locNo()]; I.setValueUnchecked(Loc.changeLocNo(NewLocNo)); I.setStart(I.start()); } } /// Find an iterator for inserting a DBG_VALUE instruction. static MachineBasicBlock::iterator findInsertLocation(MachineBasicBlock *MBB, SlotIndex Idx, LiveIntervals &LIS) { SlotIndex Start = LIS.getMBBStartIdx(MBB); Idx = Idx.getBaseIndex(); // Try to find an insert location by going backwards from Idx. MachineInstr *MI; while (!(MI = LIS.getInstructionFromIndex(Idx))) { // We've reached the beginning of MBB. if (Idx == Start) { MachineBasicBlock::iterator I = MBB->SkipPHIsLabelsAndDebug(MBB->begin()); return I; } Idx = Idx.getPrevIndex(); } // Don't insert anything after the first terminator, though. return MI->isTerminator() ? MBB->getFirstTerminator() : std::next(MachineBasicBlock::iterator(MI)); } /// Find an iterator for inserting the next DBG_VALUE instruction /// (or end if no more insert locations found). static MachineBasicBlock::iterator findNextInsertLocation(MachineBasicBlock *MBB, MachineBasicBlock::iterator I, SlotIndex StopIdx, MachineOperand &LocMO, LiveIntervals &LIS, const TargetRegisterInfo &TRI) { if (!LocMO.isReg()) return MBB->instr_end(); Register Reg = LocMO.getReg(); // Find the next instruction in the MBB that define the register Reg. while (I != MBB->end() && !I->isTerminator()) { if (!LIS.isNotInMIMap(*I) && SlotIndex::isEarlierEqualInstr(StopIdx, LIS.getInstructionIndex(*I))) break; if (I->definesRegister(Reg, &TRI)) // The insert location is directly after the instruction/bundle. return std::next(I); ++I; } return MBB->end(); } void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex StartIdx, SlotIndex StopIdx, DbgValueLocation Loc, bool Spilled, unsigned SpillOffset, LiveIntervals &LIS, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI) { SlotIndex MBBEndIdx = LIS.getMBBEndIdx(&*MBB); // Only search within the current MBB. StopIdx = (MBBEndIdx < StopIdx) ? MBBEndIdx : StopIdx; MachineBasicBlock::iterator I = findInsertLocation(MBB, StartIdx, LIS); // Undef values don't exist in locations so create new "noreg" register MOs // for them. See getLocationNo(). MachineOperand MO = !Loc.isUndef() ? locations[Loc.locNo()] : MachineOperand::CreateReg(/* Reg */ 0, /* isDef */ false, /* isImp */ false, /* isKill */ false, /* isDead */ false, /* isUndef */ false, /* isEarlyClobber */ false, /* SubReg */ 0, /* isDebug */ true); ++NumInsertedDebugValues; assert(cast(Variable) ->isValidLocationForIntrinsic(getDebugLoc()) && "Expected inlined-at fields to agree"); // If the location was spilled, the new DBG_VALUE will be indirect. If the // original DBG_VALUE was indirect, we need to add DW_OP_deref to indicate // that the original virtual register was a pointer. Also, add the stack slot // offset for the spilled register to the expression. const DIExpression *Expr = Expression; uint8_t DIExprFlags = DIExpression::ApplyOffset; bool IsIndirect = Loc.wasIndirect(); if (Spilled) { if (IsIndirect) DIExprFlags |= DIExpression::DerefAfter; Expr = DIExpression::prepend(Expr, DIExprFlags, SpillOffset); IsIndirect = true; } assert((!Spilled || MO.isFI()) && "a spilled location must be a frame index"); do { BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE), IsIndirect, MO, Variable, Expr); // Continue and insert DBG_VALUES after every redefinition of register // associated with the debug value within the range I = findNextInsertLocation(MBB, I, StopIdx, MO, LIS, TRI); } while (I != MBB->end()); } void UserLabel::insertDebugLabel(MachineBasicBlock *MBB, SlotIndex Idx, LiveIntervals &LIS, const TargetInstrInfo &TII) { MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS); ++NumInsertedDebugLabels; BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_LABEL)) .addMetadata(Label); } void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, const TargetInstrInfo &TII, const TargetRegisterInfo &TRI, const SpillOffsetMap &SpillOffsets) { MachineFunction::iterator MFEnd = VRM->getMachineFunction().end(); for (LocMap::const_iterator I = locInts.begin(); I.valid();) { SlotIndex Start = I.start(); SlotIndex Stop = I.stop(); DbgValueLocation Loc = I.value(); auto SpillIt = !Loc.isUndef() ? SpillOffsets.find(Loc.locNo()) : SpillOffsets.end(); bool Spilled = SpillIt != SpillOffsets.end(); unsigned SpillOffset = Spilled ? SpillIt->second : 0; // If the interval start was trimmed to the lexical scope insert the // DBG_VALUE at the previous index (otherwise it appears after the // first instruction in the range). if (trimmedDefs.count(Start)) Start = Start.getPrevIndex(); LLVM_DEBUG(dbgs() << "\t[" << Start << ';' << Stop << "):" << Loc.locNo()); MachineFunction::iterator MBB = LIS.getMBBFromIndex(Start)->getIterator(); SlotIndex MBBEnd = LIS.getMBBEndIdx(&*MBB); LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB) << '-' << MBBEnd); insertDebugValue(&*MBB, Start, Stop, Loc, Spilled, SpillOffset, LIS, TII, TRI); // This interval may span multiple basic blocks. // Insert a DBG_VALUE into each one. while (Stop > MBBEnd) { // Move to the next block. Start = MBBEnd; if (++MBB == MFEnd) break; MBBEnd = LIS.getMBBEndIdx(&*MBB); LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB) << '-' << MBBEnd); insertDebugValue(&*MBB, Start, Stop, Loc, Spilled, SpillOffset, LIS, TII, TRI); } LLVM_DEBUG(dbgs() << '\n'); if (MBB == MFEnd) break; ++I; } } void UserLabel::emitDebugLabel(LiveIntervals &LIS, const TargetInstrInfo &TII) { LLVM_DEBUG(dbgs() << "\t" << loc); MachineFunction::iterator MBB = LIS.getMBBFromIndex(loc)->getIterator(); LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB)); insertDebugLabel(&*MBB, loc, LIS, TII); LLVM_DEBUG(dbgs() << '\n'); } void LDVImpl::emitDebugValues(VirtRegMap *VRM) { LLVM_DEBUG(dbgs() << "********** EMITTING LIVE DEBUG VARIABLES **********\n"); if (!MF) return; const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo(); SpillOffsetMap SpillOffsets; for (auto &userValue : userValues) { LLVM_DEBUG(userValue->print(dbgs(), TRI)); userValue->rewriteLocations(*VRM, *MF, *TII, *TRI, SpillOffsets); userValue->emitDebugValues(VRM, *LIS, *TII, *TRI, SpillOffsets); } LLVM_DEBUG(dbgs() << "********** EMITTING LIVE DEBUG LABELS **********\n"); for (auto &userLabel : userLabels) { LLVM_DEBUG(userLabel->print(dbgs(), TRI)); userLabel->emitDebugLabel(*LIS, *TII); } EmitDone = true; } void LiveDebugVariables::emitDebugValues(VirtRegMap *VRM) { if (pImpl) static_cast(pImpl)->emitDebugValues(VRM); } bool LiveDebugVariables::doInitialization(Module &M) { return Pass::doInitialization(M); } #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) LLVM_DUMP_METHOD void LiveDebugVariables::dump() const { if (pImpl) static_cast(pImpl)->print(dbgs()); } #endif